Well pump



sealing element is Patented Dec. 4, 1934 PATENT OFFICE WELL PUMP JohnPenrod, Okmulgee, Okla., assignor of one" half to Robert D. Thompson,Okmulgee, Okla.

Application December 20, 1929, Serial No. 415,550

14 Claims.

This invention relates to fluid lifts especially adapted for use in therecovery of oil and the like from wells.

One of the features of .the invention resides in the provision of aspecial sealing or packing means designed to bridge the space betweenthe tubing or other fluid conduit and the upper portion of the workingbarrel, to the end that the settlement of sand intobinding engagementwith the working barrel and the foot valve thereof is inhibited, it being noted in this connection that the collection and impaction of sandabout these parts of the conventional pump has 'the effect of freezingthe pump in place and thereby preventing the later unseating of thepump.

More specifically, the invention will be found to provide simple meansby which the sealing element of the packer is expanded, radially intopressure engagement with the wall 4of or the like after the pump hasbeen seated, without the necessity of compressing the sealing elementlongitudinally.

Another feature of the invention resides in the means by which, duringthe unseating of the packer, prior, of course, to the unseating of thepump, the radial expansive force on the relieved and a longitudinalstretching force applied to the sealing element from the upper portionthereof to bring about sufficient reduction in the diameter of thesealing element to allow the sealing element to be passed freely throughthe accumulated annular body of sand, if any, above the same, and toallow of the unobstructed movement of the pump through the tubing.

Another aim of the invention is to provide a packer in which the sealingelement thereof or such other parts as may become worn from time to timemay be renewed at the well without the exercise of unusual skill or theaid of special tools.

'Ihe invention forming the subject of this application will also befound to embody a novel form of valve assembly in which the free ow offluid about all sides of the spherical valve element is allowed and inwhich excessive wear on the ball stop is avoided.

The invention contemplates a novel arrangement by which, after the pumphas been unseated, the cups or other sealing devices of the foot valveare protected from damage by the descending sand or tubing fluid above.

Other objects and advantages will become `apparent as the description ofthe invention proceeds.

the tubing In the accompanying drawings forming a part of thisapplication and in which like numerals are employed to designate likeparts throughout the same,

Figure 1 is a fragmentary vertical sectional 60 view through theimproved fluid lift, the various parts of the packer being shown in thepositions occupied immediately before the radial expansion of thesealing element thereof,

Figure 2 is a vertical detail sectional view 65 through the packer, theview illustrating the sealing element expanded radially into pressureengagement with the wall of the tubing,

Figure 3 is a detail sectional view through the packer, the sealingelement of the same being stretched longitudinally from the upperportion thereof preparatory, of course, to the unseating of the pump,

Figure 4 is a vertical detail sectional view through the upper portionof a pump equipped with the improved packer,

Figure 5 is a vertical sectional view through the intermediate portionof the pump,

Figure 6 is a vertical sectional view through the lower portion of thepump.

In the drawings wherein for the purpose of illustration is shown apreferred embodiment of the invention, the numeral 5 designates a tubingwhich, of course, is positioned within the usual casing not shown.Figures 1 and 6 illustrate that 85 a foot valve shoe '7 has connectionwith the tubing and is provided at the lower portion thereof withsuitable means by which fluid inlet means of any nature may be connectedthereto.

The foot valve body 9 is provided with pairs 90 of opposed cups 10adapted for reception in the foot valve shoe for pressure engagementwith the side wall thereof to establish a fluid tight seal between thefoot valve and the shoe. It will be seen with reference to` Figures land 6 95 that each of the several pairs of cups l0 embodies a lowerupwardly presented cup and an upper inverted or downwardly presentedcup, the upper downwardly presented cup of each pair having the loweredge thereof spaced only a slight distance above the upper edge of thelower cup of that pair so that when the pump is unseated and the fluidpreviously admitted to the tubing is rushing back into the well, theupwardly presented cups will be protected by the inverted cupsimmediately above.

In other words, the very slight distance between the opposed edges ofthe upper and lower cups of each pair of cups prevents the admission ofthe descending fluid in destructive volume into the space between thecups with the result that the upwardly presented cups are prevented frombeing turned outward and thereby rendered unfit for further efcient use.The cups of each pair may be spaced by more or less conventionalfollowers which are, of course, mounted on the valve body 9 asillustrated in Figure 6.

It is also illustrated in Figure 6 that a closed valve cage 12 isthreaded on to the reduced upper portion of the valve body 9 and isprovided with a spherical valve element 14 adapted to be elevated by theascending fluid into engagement with the converging stop arms 16 of astop connector in the nature of a bushing, the lower end of which isthreaded into the closed cage 12, while the upper end is threaded into.the lower portion of the working barrel 18.

In further adverting to the formation of the stops 16, it is pointed outthat the same are formed integral with the member 17 and that the lowerends thereof are disposed in intersecting planes cooperating in theformation of a sort of centrally located V-shaped recess adapted toreceive the upper portion of the spherical valve element 14. When thespherical valve element 14 is received within the V-shaped recess denedby the angularly disposed lower ends of the arms 16, the ball is heldthereby in a central position in the cage to allow of the free ascent ofiiuid about all sides of the ball valve element and at the same time toprevent the ball valve from beating out the side walls of the cage. Itis thus seen, that the arms 16 perform the dual purpose of allowing ofthe relatively free ascent of fluid through the cage and at the sametime protecting the side walls of the cage from destructive contact bythe ball valve. The vertical passage of fluid about all sides of thespherical valve element in substantially uniform volume has the effectof holding the ball valve centrally with the upper surface thereof inengagement with the angularly disposed lower ends of the arms 16. Inthis manner, the fluid conducting capacity of the closed cage 12 isincreased and the life of the cage 12 and the stops is prolongedgreatly.

The plunger which reciprocates within the working barrel 18 has at thelower portion thereof a traveling valve body 20 of tubular formation andupon which a suitable number of cups 21 or other suitable sealingdevices are mounted for uid tight contact with the wall of the workingbarrel. The cups 21 and the customary followers thereof are held/firmlyon the body 20 by a combined fastening and bumping nut 22. 'The nut 22is shown in Figure 6 to be positioned immediately above the connector 17so that by lowering the plunger, the nut 22 is caused to have strikingengagement with the connector or bushing 17 to prevent further expansionof the packer to be described.

The upper portion of the packing body 20 is externally threaded forconnection with the closed traveling valve cage 24 within which aspherical valve element 26 operates. The upward movement of thespherical valve element 26 is limited by a pair of converging stop armscorresponding in construction to the arms 16 and depending from aconnector or bushing 28.l

As shown in Figure 5, the member 28 is internally threaded forconnection with a tubular piston or plunger body 30 upon the lowerportion of which a packing device 31, preferably embodying a number ofpacking rings, is mounted. The packing device 31 is confined between theupper the annular groove thus defined between the end of the connector28 and the underside of a thimble 32. 'Ihe thimble 32 is urged downwardinto pressure engagement with the packing 31 by an expansion spring 33,the upper end of which abuts a nut 34 threaded on the intermediateportion of the piston body 30. It might be noted that the upper surfaceof the thimble 32 is recessed not only for the purpose of receiving thelower convolutions of the spring 33, but to collect such sand as maywork by the parts above.

The piston body 30 carries upper and lower piston sleeves or liners 36and 37 respectively, spaced by a spacing sleeve 39 mounted on the pistonbody between the opposed ends of these parts. Figure 5 illustrates thatthe upper terminal of the piston sleeve 37 is spaced below the opposedend of the upper piston sleeve 36 and cooperates therewith in theformation of an annular oil receiving groove to the end that a uid sealis established between the intermediate portion of the plunger and thewall of the working barrel.

Particular attention is directed to the fact that 10J opposed ends ofthe piston sleeves 36 and 37 provides an entrance to an annular sandreceiving pocket 40, in the upper portion of the lower piston sleeve.Such sand as may work its way down between the working barrel and theupper piston sleeve 36 is caused to enter the annular sand trap 40 byway of the annular groove immediately above this trap with the resultthat the sand is held against further descent and destructive wear onthe pump parts located below.

The upper ends of the sleeves or liners 36 and 37 are bevelled to sharpedges for scraping engagement with the wall of the working barrel tocombat the descent of sand between the plunger and the barrel.

The major portion of the sand settling from the tubing iiuid is directedby the bevelled upper end of the sleeve`36 into the piston or plungerbody 30 by way of the open upper end thereof. Of course, such sand as isreceived within the piston body 30 is pumped out when the operation ofthe pump is resumed.

'Ihe small amount of sand that may find its way between the liner 36 ofthe working barrel is directed by the bevelled upper end of the liner 37into the annular sand trap 40 where it is held against -destructive wearon the pump parts located below.

Figure 5 illustrates that the upper portion of 130 the piston body 30 isexternally threaded for connection with an outlet cage 42, the outletcage being formed with a plurality of longitudinally extending radiallydisposed outlet ports discharging into the recessed or cupped upper endof the liner 36.

It is important to observe that the working barrel and the plungertherein are introducedV into the tubing and are withdrawn therefrom as aunit so that the working barrel itself is caused to protect therelatively thin and bevelled scraping upper edges of the piston sleeves36 and 37 from damage by contact with the joints of the tubing or bysuch obstructions as may be present in the wall of the tubing.

Coming now to the packer embodied in the invention, attention is invitedto Figures 2, 3 and 4 in which it is shown that a tubular latching orclutching member 44 is threaded into the upper portion of the barrel andserves as a sup- 150 port for a mandrel sleeve 46, the said mandrelsleeve beingprovided with a plurality of spaced more or less parallelincisions opening out through the upper end thereof to dene an annularseries of leaf springs adapted to be brought into pressure engagementwith the surrounding sealing element 48. The sealing element 48 is oftubular formation and may be of any one of a number of materials foundadaptable for the purpose. For example, rubber or leather may beemployed or if desired a composition of rubber and a fabric maybe used.

In carrying out the invention, the upper portion of the latching member44 may be provided with an annular ange or lip spaced outwardly from thelower portion of the mandrel sleeve 46 and cooperating therewith in theformation of an annular groove receiving the lower portion of thetubular sealing element 48. The lower portion of the mandrel sleeve 46is reduced externally in diameter to dene an annular shoulder into whichthe lower portion of the sealing element 48 is pressed by a. retainingring 49. Otherwise expressed, the retaining ring 49 which is slippedeasily on to the lower portion of the sealing element 48, constricts thediameter of the lower portion of the sealing element 48 and therebyforces the sealing element into pressure engagement with the shoulder 45with the result that the lower portion of the sealing element isanchored to the adjacent portion of the mandrel sleeve.

The upper portion of the tubular sealing element 48 is shown to besurrounded by a retaining ring 50 which has the effect of constrictingthe upper portion of the sealing element and thereby forming an annularstop shoulder per- `forming a major part in the longitudinal stretchingoperation as will be described.

As illustrated in Figures 2 and 3, the wall of the bore of the mandrelsleeve 46 is flared outward at a point between the ends of the mandrelsleeve to define an intermediate internal camlike surface for engagementby the diametrically enlarged upper portion or head of a tubular mandrel52. Also, by forming the mandrel sleeve 46 with the internal annularcam-like surface, the annular series of leaf springs constituting amajor portion of the mandrel sleeve have the upper portions thereofreduced in thickness and consequently rendered more yieldable.

In preparing the various parts for installation into the well, the heador enlarged upper portion of the mandrel 52 is positioned Within theinternally enlarged upper portion of the mandrel sleeve 46 with theresult that, until further adjustment is made, the mandrel sleeve 46will remain in the normal unexpanded position disclosed in Figure 4 andthe sealing element will occupy a position spaced inward from the wallof the tubing 5.

The mandrel 52 carries a combined cap and contact member 56 having askirt 58 adapted to receive the upper portion of the sealing element 48to exclude settling sand from the space within the sealing element. Whenthe device is set as disclosed in Figure 2, the depending skirt 58 has agenerous overlap with the upper portion of the sealing element so thatthe incursion of sand into the space within the sealing element isinhibited.

No effort has been made to provide a fluid tight seal between thedepending skirt 58 and the upper portion of the sealing element 48 forthe reason that the fluid pressure prevailing within the sealing element48 will be the same or approximately the same as that prevailing withinthe tubing with the result'that there will be no 'circulation of fluidthrough the sealing element.

In Figure 4 it is shown that the latching springs of the member 44 areprevented from being fouled by settling sand rst, by the fact that thesame are received within and are protected by the upperportion of theworking barrel and second, by the fact that the latching springs extendinward at an angle from the working barrel. Also, the spaces between thelatching springs are open at the lower ends thereof to allow of the freedescent of such sand as may enter the barrel by way of the packer.

A sand arrester 60 is movably located on the valve rod 62 and whenresting on the member 56 will prevent the descent of sand through thespace between the valve rod and the mandrel 52. The member 60 not onlyserves as a means for arresting the descent of sand but as a motiontransmitting means during the seating of the pump and the subsequentexpansion of the sealing element of thepacker into pressure engagementwith the wall of the tubing 5. In explaining this latter purpose of themember 60, it is pointed out that the valve rod 62 is formed with anannular enlargement 66 or other contact means adapted to engage themember 60 at the upper end thereof and thereby force the same downwardinto driving engagement with the cap 56 of the mandrel 52. As will bedescribed, the downward force thus imparted to the mandrel istransmitted through the working barrel 18 to seat the foot valve of thepump.

In Figures 2, 3 and 4 is it illustrated that the latching member 44depends into the upper portion of the working barrel and has the barrelencircled portion formed with an annular series of longitudinalincisions opening out through the lower end thereto form an annularseries of longitudinal leaf springs, the lower portions of which areextended inwardly to define latching dogs 68.

'Ihe mandrel is shown to be provided at a point spaced at a slightdistance from the lower end thereof with an annular shoulder '70, thelower surface of which is slightly bevelled to rest on the annularseries of latching dogs 68 before the seating of the foot valve.

In preparing for the installation of the pump, the various parts thereofare positioned as disclosed in Figures 1, 4, 5 and 6 in which theannular enlargement or shoulder 70 of the mandrel is held in arelatively elevated or retracted position by the inwardly extendingspring dogs 68. Of course, with the parts in this position the sealingelement 48 is in its unexpanded position so that during the lowering ofthe pump into the well, the sealing element will freely pass the jointsof the tubing and such obstructions as may be present on the wall ofthe-tubing.

Now, continued descent of the pump during the installation thereof, willresult in the entrance of the foot valve into the shoe 7 and during suchentrance of the foot valve into the shoe, the seating force istransmitted through the valve rod 62, the enlargement 66 thereof, hesand arrester 60, the cap 56, the mandrel 52, the spring dogs 68, theworking barrel 18, and the foot valve, all in the order mentioned.

It will be seen that when the foot valve is seated and is therebyprevented from further descent, the continuing downward forcetransmitted through the valve rod 62 will result in overcoming thestrength of the spring pressed dogs 68 with the result that the annularshoulder '70 will descend to the position' shown in Flgure 2. Beforegoing on with the description of the manner in which the packer isexpanded, it might be noted that the resistance to the seating of thefoot valve in the shoe 'I is substantially less than the combinedstrength of the spring dogs 68: 'I'hus during the seating of the footvalve the shoulder 70 .wiil remain in engagement with the upper sides ofthe dogs 68 in the manner disclosed in Figure 4.

However, when the foot valve is fully seated as disclosed', the springdogs 68 are sprung outwardly to allow of the descent of the mandrel 52under the influence of the weight above and the enlarged headof the samewill engage the intermediate cam-like surface of the wall of the bore ofthe mandrel sleeve 46 and thereby expand the sealing element radiallyinto pressure contact with the wall of the tubing.

As the enlarged head of the mandrel 52 reaches or approaches the limitof its eilective down stroke with respect to the mandrel sleeve 46, theannular shoulder '70 oi' the mandrel will occupy a position immediatelybeneath the inwardly projecting latching dogs 68 with the result thatthe mandrel is held in this position by such dogs until releasedpreparatory to the unseating of the pump.-

It might be noted that before the mandrel 52 can descend to a pointsutilcient tc damagethe surrounding parts, the bumper nut 2'2 carried bythe lower portion of the plunger will engage the upper end of the member17 to limit further descent of the plunger.

With the pump thus seated, and the sealing element of the packerexpanded radially into pressure engagement withv the wall `of thetubing, the descent of sand to the region of the foot valve of the pumpis prevented so that the later unseating of the pump is simplified andrendered much less uncertain than has heretofore been the case.Particular attention might be directed to the fact that the pressuretight contact of the sealing element-48 of the packer with the tubing iseffected without endwise pressure on the packer or perceptible change inthev positions of the ends of the sealing element.

When it is desired to unseat the pump, for any one of a number ofreasons, the first step is to withdraw the packer 'from pressureengagement with the wall of the tubing and to accomplish this, theupstroke of the pump is exceeded a suilicientextent to bring theshouidered lower portion '14 of the valve rod 62 into bumping engagementwith the bumper nut 'i6 threaded on the lower portion of the mandrel 52.This has the eeet of raising the mandrel 52 to the position disclosed inFigure 3. It might now be pointed out that the bevel or angle oi' theupper surface of the shoulder 'I6 is greater than that of the lowersurface of the shoulder so that less resistance is offered to the upwardmovement of the mandrel than was offered to the downward movementthereof.

When the mandrel is thus moved upward preparatory to the unseating ofthe pump, the outward pressure on the mandrel sleeve 46 is releved andthe sealing element 48 allowed to contract. However, it may be that as aresult of prolonged radial expansion of the sealing element, theelasticity thereof is impaired to a point where the sealing element willnot of its own accord resume its'original smaller diameter.

To provide for such a contingency, the enlarged upper portion of the.mandrel, upon nearing thecompletion of its upstroke, is caused to engagethe internally shouldered or constricted upper portion of the sealingelement and thereby stretch the sealing element from the'upper endthereof. This stretching force applied to the sealing element from theupper portion thereof will rst, detach the sealing element fromengagement with the wall of the tubing and sec-I ond, will elongate thesealing element sufficiently to cause the same to resume its originaldiametrical formation.

It is important to observe that the longitudinal stretching of thetubular sealing element, as referred to in the immediately precedingparagraph, is limited byv reason of the fact that continued upwardmovement of the valve rod` 62 will cause the bumper nut 76 on the lowerend of the mandrel to engage the lower end of the latch member 44. This,of course, exerts an upward pull on theworking barrel to withdraw thefoot valve from the shoe 7. t

Adverting again to the advantage of stretching the sealing element 48and thus reducing the diameter of the same, preparatory to unseat-` ingthe pump, itis pointed out that the packing is allowed to travel upthrough the wall of accumulated sand immediately above. In explainingthis point, attention might be directed to Figures 2 and 3 in which itis illustrated that during the use of the pump a wall of sandaccumulates and tightly packs between the cap 56 and the tubing andinterferes with the removal of the pump unless, of course, the sealingelement has a diameter less than that of the opening through the sand,the said' opening being formed by the hood 58 of the cap 56.

When the pump is withdrawn to the surface for repair or any otherreason, it is a simple matter to detach the cap 56 and latch 50 and thento unscrew the mandrel sleeve 46 from the latching member 44 so that theretaining ring 49 may be removed from the lower end of the sealingelement. This allows of the quick disconnection of the sealing element48 and of the substitution of a new one. This may be done at the wellwithout the exercise of special skill or the aid of special tools.

Having thus described the invention, what is claimed is:

1. In a structure of the character described. a working barrel, alatching member attached to the working barrel and having leaf springsdepending into the working barrel for protection thereby and beingformed with dogs, a packer having a sealing element and a mandrel forexpending the sealing element, said mandrel being formed with a shoulderdefining upper and lower contact surfaces adapted for engagement by saiddogs.

2. In a structure of the character described, a barrel, a latchingmember attached tothe barrel and having a plurality of leaf springsdepending into the barrel and formed with dogs,

a sealing element, a mandrel for expanding the vided with means in aworking barrel, a latching member carried by the working barrel andhaving a plurality of spring members depending into the barrel andformed with dogs, a mandrel extending through the latching member andhaving means for motion transmitting engagement with the upper surfacesof said dogs to move the barrel downward, and a lowering mechanismengaged with said mandrel.

4. In a structure of the character described, a barrel, a latchingmember having spring vmembers depending into the barrel and formed withdogs, a mandrel extending through the latching member and having meansfor motion transmitting engagement with the upper surfaces of said dogsto move the barrel downward, a lowering mechanism engaged with saidmandrel, and means associated with said lowering mechanism to move themandrel upward.

5. In a structure of the character specified, a barrel, a latchingmechanism carried by the barrel and having separate spring armsdepending into the barrel and formed with dogs,'a mandrel having anannular enlargement defining upper and lower contact surfaces forengagement with said dogs, a sealing element associated with saidmandrel, a foot valve carried by said barrel, and a lowering mechanismto move said mandrel, the latching mechanism and the barrel downward toseat said foot valve, the strength of said spring arms being superior tothe resistance to the seating of the foot valve whereby the foot valveis seated prior to the yielding of the spring arms and the consequentoperation of said mandrel to expand said sealing element.

6. In a structure of the character specified, a barrel, a latchingmechanism carried by the barrel and having separate spring arms formedwith dogs, a mandrel having an annular enlargement defining upper andlower contact surfaces for engagement with said dogs, a sealing elementassociated with said mandrel, a foot valve carried by said barrel, alowering mechanism to move said mandrel, the latching mechanism and thebarrel downward to seat said foot valve, the strength of said springarms being superior to the resistance to the seating of the foot valvewhereby the foot valve is seated prior to the yielding of the springarms and the consequent operation ofvsaid mandrel to actuate saidsealing element, said mandrel being provided with means to stretch saidsealing element from the upper portion thereof.

7. In a structure of the character specified, a sealing element oftubular formation, a radially expansible mandrel sleeve within thetubular sealing element and increased in internal diameter toward theupper end thereof thereby defining an intermediate cam, a mandrel havinga spreader initially positioned in the internally enlarged portion ofsaid mandrel sleeve and adapted for movement into engagement with thecam surface of the sleeve to expand the sleeve and the sealing elementradially, the upper portion of said sealing element being prothe path oftravel of and adapted to be engaged by said spreader when moved upwardto stretch the sealing element from the upper end thereof.

8. In a structure of the character specified, a sealing element, aradially expansible mandrel sleeve within the sealing element andincreased in internal diameter toward the upper end thereof therebydening an intermediate cam, a

mandrel having a spreader initially positioned in the internallyenlarged portion of said mandrel sleeve and adapted for movement 'intoengagement with said cam surface to expand the sleeve and the sealingelement radially, the upper portion of said sealing element beingprovided with means in the path of travel of and adapted to be engagedby said spreader when moved upward to stretch the sealing element fromthe upper end thereof, a latching mechanism having means restrictingendwise movement of the mandrel in both directions, there being meanslimiting upward movement of the mandrel and consequent stretching of thesealing element.

9. In a structure of the character specified, a sealing element oftubular formation, a retaining ring detachably embracing the upperportion of said sealing element thereby constricting the same and deningan internal shoulder, a mandrel movable within said sealing element toexpand the same and having means to detachably engage said internalshoulder of the sealing element to stretch the sealing element from theupper end thereof, and a latching member to engage the mandrel toreleasably secure the mandrel in advanced or retracted position.

l0. In a structure of the character specified,

a body, a mandrel sleeve on the body and formed with spring arms havingthe inner surfaces thereof formed with cams, a sealing elementsurrounding the mandrel sleeve, a mandrel having a spreader to engagesaid cams and thereby expand the sealing element radially, a retainingring positioned detachably on the upper portion of said sealing elementto constrict the same, the spreader of said mandrel being adapted toengage the constricted upper portion of said sealing element to stretchthe sealing element from the upper portion thereof, a barrel below saidsealing element and having a foot valve, and means acting through themandrel to seat said foot valve.

11. In a pump, a working barrel having a foot valve, a latchingmechanism carried by the barrel, a sealing element carried by saidlatching mechanism, a mandrel sleeve carried by the latching mechanism,a mandrel within said sleeve and having a spreader to expand the sameand th'e sealing element radially, said mandrelbeing provided with meansengaged by said latching mechanism and yieldingly held in a retractedposition thereby, and a lowering device acting through said mandrel, thelatching mechanism and said barrel to seat said foot valve.

12. In a pump for use in wells, a barrel, a plunger in said barrel andprovided with a sharpened edge, a latching mechanism depending into thebarrel, a mandrel extending through said latching mechanism andrestrained thereby, a J

having a greater degree of incline than the other contact shoulder tooffer less resistance to movement of the mandrel than does the otherconrigidly to the working barrel and having spring dogs dependingl intothe barrel and protected thereby, amandrel having` a shoulder torengagement by said spring dogs, a sealing element associated with saidmandrel, and a-valve rod movable through said mandrel and having means'to retract the mandrel.

. JOHN PENROD.

